Dave Wilshere

30oz in the tail does not add up. What’s in the nose to make it that nose heavy?

roydefiant

The CB 400, RX batteries in the nose. Also my cockpit fixtures definitely weigh over a pound.

roydefiant

I am making the weight easily removable. Ideally perhaps this winter I can make the stinger removable and move ECU and afterburner batteries back there and getting lighter ejection seats printed.

roydefiant

The CB400 alone weighs 10oz.

Edgar Perez

My Feedback: (13)

I think I'm going to finally maiden my CARF SU-30 next week (bough plane second hand and had to do a lot of fixes..) The plane has 5.5. inch which causes to have excessive toe-in in order to fit the wheel well and not hit the doors. The mount of toe-in means that I need almost full power just to get it moving. Since I have two 160N turbines, I can brute force the takeoff. However I just don't think this will last without something coming off eventually.
Is there anyone using the 5.5 inch and can share any "tricks" to reduce the toe-in?
I read that many are using the Robart (?) 5 inch wheel. I many need to go that route, but i think that means I need to change the hubs and brakes system. The plan currently have converted Down & Locked with the brakes based on micro-servos...

Maggoo811

Finally after a few problems with the turbines I had some real nice flights at the weekend.

CG is 10mm in front of the main tube - still feels a little nose heavy...

Dave Wilshere

My guys either used 5” Dubro or Sullivan with the original set up. The later electric set up with thin wheels works best.

Edgar Perez

My Feedback: (13)

I have the thin wheels, but they are ~5.5 inches. Don't fit in the wheel well without the huge toe-in

Dave Wilshere

Then you need to shim the units....

roydefiant

So again taking note from across the pond, I revisited the concept of adding lead to the tail. Moving the batteries back into the stinger would eliminate the need for adding lead to the model. To accomplish this, telescoping carbon fiber tubes were glued in place and secured between an added former in the stinger and between 2 formers in the fuse. A slotted 3D printed former was glued into the back after further reinforcement in the stinger. A removable sliding tray was made that will hold the lipos and make it easy to remove to charge outside the model. A single screw comes up from the bottom of the fuse to secure the stinger from sliding back.

Auburn02

My Feedback: (1)

Nice ingenuity there but I cannot wrap my head around the need for so much weight in the rear. What engines are you using?

roydefiant

Jets Munt 166. I have a full custom printed cockpit which looks great but is a little heavy. In addition my CB400 is in the nose (300 grams) along with the Rx batteries. The ECU batteries and afterburner lights battery will go in the back

TheFishLA

I'm surprised to find out that some needed to add weight in the back. I'm building mine at the moment with tail vectoring, 2xjets munt 166.
I did some initial balancing (still no batteries, cockpit or UATs installed...) and looks like my nose requires about 2.7KG in order to get a CG of the front leading edge of the spar. What am I missing?

Dave Wilshere

You have the batteries in the nose? you would need tail weight. You will probably go back on CARF's balance point too. Any fuel in the tank doing the balance? If not you are wasting your time doing the pre-check.
We have ended up with batteries around the removable inlet section

Dave

TheFishLA

that was without batteries, UAT and cockpit, no fuel tanks in yet. I'm guessing Those will weight:
500g - batteries
500g - cockpit
500g - UAT
500g - fuel tanks with some landing fuel.

So I'm still short about 700g. I just want to see if I'll need to add a front tray in the cone or not.

Dave Wilshere

You said tail weight in the op.? No batteries will be in the nose cone. Add landing fuel before balancing as its in front of the balance point.

Andrew Bird

I started with my batteries up front and quickly found the manual CG was pretty nose heavy for my liking. I have a really nice but slightly heavy 3d printed cockpit as well though. My batteries are now mostly in the middle of the plane - initially I stuffed the stinger in the tail with quite a bit of lead. The plane seems very robust over CG.

skymaster68

My Feedback: (4)

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We have ended up with batteries around the removable inlet section

Dave[/QUOTE]

good Idea placing the batteries in that area, never thought on doing that... any pictures of that set up Dave?

Dave Wilshere

I don’t think I have any pictures, but a ply plate bonded to the top skin with Velcro straps tapped was all it was.

Dave

butler-campers

Are you shutting the power " off " on the nose gear steering servo when the nose gear is retracting in or out. I have the electric carf gear. I bought the plane 2e hand. I notice that the steering point on the nose gear moves when the retract is going in or out.

Best regards Maikel

Andrew Bird

I've got the CARF electric gear and when retracted, you set the servo position through the controller. It binds unless you've set it to the point where there's no load on it.

su27flanker

Hello everyone,

I've narrowed my next plane down to the Carf Su-30 or L-39, I really like the Su-30 however its a lot of money for myself to spend so I'm just trying to decide whats best for me.

How has everyone found the Su-30 reliability? can i fly this most second weekends no problem or is there a lot of maintenance with the gear, doors etc. I like how simple the L-39 is with 2 moving gear doors etc but i like the reliability of the twin turbine idea on an expensive jet anf Flankers have been my life long fav jet!
Is the Su-30 still easy to fly / land vs the l-39?

Dave Wilshere

I’ve flown them both, both relatively easy to fly and handle. The SU will require more maintenance and the gear is more ‘fussy’ than the L-39, but both will operate as weekend machines. If your vehicle is large enough the SU-27/30 assembles quicker at the field.
Both aircraft have had updates to the gear over the last 12 months, so a lot of experience here won’t be on the current equipment

Dave

su27flanker

Many thanks Dave, have you flown the thrust vector version of the su-27/30?
I'm not a 3d guy but I do enjoy the extra manoeuvrability from videos ive seen on YouTube, but over all just looking for a big floaty light scale jet so either setup would be still great I’m sure!

Dave Wilshere

No, but one of my friends has one ( he flies the opposite mode to me) we converted after a season non vectored. It has two JetCat P-140’s so not enough to hover properly, but it does nice flat spins, and back flips tighter than non vectored.